1. Field of the Invention
The present invention relates to a feedback system applied in Human-Machine Interface (HMI) for identifying movement and intensity of an external force.
2. Description of Related Art
Human-Machine Interface (HMI) plays a very important role in the development of the multimedia applications and directly influences the operating feelings of end users. Early, the only HMI is a keyboard which is constrainedly suitable for the applications based on command line interface and text interface, while is insufficient for processing graphics. In 1980s, mouse widely used in Mac computer accelerated the development of the graphics user interface. Till now, mouse and Windows operation system maintain major market of the multimedia applications. One of the disadvantages of mouse is its big profile so that it is not suitable for being used in small mobile equipments, such as handset, PDA and Notebook etc. Besides, a reasonable large space is needed for the movement of the mouse, which restricts the usage thereof. In 1990s, Ted Selker invented a TranckPoint (see U.S. Pat. No. 5,867,808) which was widely used in Thinkpad series notebook computers of IBM. After year 1994, George E. Gerpheide invented a touchpad (see U.S. Pat. No. 6,222,528) which was firstly used in PowerBook series notebook computers of Apple Inc. The above-mentioned two invention creations accelerate the development of the HMI which is applied in notebook computers.
Handheld terminals raise higher requests about the profile of input systems of the HMI, after entering into the mobile multimedia era. Japanese Sunarrow Ltd. had invented a kind of 3D sensor based on the capacitance-based touch theory (see U.S. Patent Publication No. 2007/0257886). Such products have been widely used in Nokia handsets. Besides, Veganov invented a handle operation system based on MEMS sensor (see U.S. Patent Publication No. 2009/0237275).
With the development of technologies, developing trends of the HMI are low profile, low cost, good interaction and friendly user experience, in order to be suitable for the rapid growth of consumer electronics and mobile handheld terminals. Hence, an improved feedback system for identifying movement and intensity of an external force is desired.